2003 Yamaha YFM400FAR Kodiak Factory Service Manual, Page 152Get this manual
CYLINDER AND PISTON
2.Measure: Piston-to-cylinder clearance Measurement steps: 1st step: Measure the cylinder bore "C" with the cylinder bore gaugeNOTE: Measure cylinder bore "C" by taking side-toside and front-to-back measurements of the cylinderThen, find the average of the measurementsCylinder bore "C" Maxtaper "T" Out of round "R" "C"= maximum of D1D6 "T"= maximum of D1, or D2 maximum of D5 or D6 "R"= maximum of D1, D3 or D5 minimum of D2, D4 or D6